Weka  (Gallirallus australis)

Weka can adapt to a wide range of conditions, persist in highly modified habitats, and be very productive (6). However, despite this, the weka appears to also be susceptible to rapid population declines and local extinctions, the causes of which are complex, and vary between each region (5) (6). The clearance and degradation of many forests and wetlands reduces numbers of weka, as does introduced mammals which prey on the weka; adults are taken by ferrets and domestic dogs, and chicks and eggs are eaten by stoats, cats and rats (5) (6). Introduced species also affect the weka by competing for food sources such as fruit and invertebrates (6). In some areas a significant number of weka are killed by road traffic, and in others, weka die after consuming poisoned bait laid for possum and rabbit control (5) (6). Extended periods of drought also contribute to a decline in weka numbers in some regions (6). Historically, the weka was hunted by some Maori and early European explorers, their curious nature making them relatively easy to catch. They were used for food, perfume, oil and feathers, but today the weka is only legally harvested on the Chatham Islands (7).

The weka is an unusual species in conservation terms, in that whilst in some regions it is threatened, in other areas it can become a problem to other threatened wildlife, especially when they have been introduced to an island outside their natural range (6). Any conservation measures need to take these two opposing problems into account. The New Zealand Department of Conservation Weka Recovery Plan was approved in 1999, which outlines different management options and a work plan, to promote the recovery of the weka (6). The plan includes actions such as determining the exact distribution and status of all subspecies, researching the impacts and management of threats, and establishing further populations to ensure that each subspecies has at least one large mainland population and three island populations (5).